• Korean Journal of Microbiology
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• v.27 no.1
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• pp.10-15
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• 1989

The plasmid pKOneo, containing SV40 transcriptional promoter, has been used in the mouse tumorigenicity assay for oncogene studies. This assay employs a cotransfection of NIG3T3 fibroblast cells with the desired DNA and the plasmid pKOneo. This oncogene assay, however, has been speculated due to the SV40 transcriptional promoter in the plasmid pKOneo. This research was designed to investigate if the plasmid pKOneo alone is capable of transforming NiH3T3 fibroblast cells. The NIH3T3 subclones were established after the NIH3T3 cells were transfected with the plasmid pKOneo alone. The estabilished NIH3T3 subclones, containing the exogeneous plasmid pKOneo in their chromosomes, were examined for their expression of transformation-associated parameters. The results indicate that this plasmid pKOneo alone has positive effects on transformation of NIH3T3 cells after integration into cellular chromosomes.

• The Journal of the Korean Society for Microbiology
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• v.22 no.2
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• pp.167-174
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• 1987

N-myc, a DNA sequence related to the oncogene c-myc, was found to be amplified in untreated primary neuroblastomas and the amplification appeared to be associated with advanced disease at diagnosis and rapid tumor progression. Synthetic peptides have been useful immunogens for generating antisera and monoclonal antibodies to a number of native proteins. In order to identify myc-related protein in the tumor cells, an antiserum against a synthetic hexapeptide (-Glu-Asp-Ile-Trp-Lys-Lys-), whose sequence corresponds to a part of the exon 2 of oncogene N-myc, was prepared by immunizing a rabbit with BSA-conjugated peptide. After ammonium sulfate precipitation and affinity column chromatography, it appeared to be specific to the peptide. Strong nuclear staining in immunoperoxidase method using this serum was observed in both human promyeloid leukemic cell line, HL-60(containing high c-myc copy number), and human neuroblastoma cell line, LA-N-5 (containing high N-myc copy number), whereas LA351 (human lymphoid cell line) cells did not react with the serum. This reaction was completely abrogated by incubating the antiserum with soluble excess peptide. These data suggest that the protein encoded by N-myc could be localized in the nucleus as c-myc protein and this antiserum can be used to detect myc-related tumor cells in clinical samples and to determine if the N-myc expression correlates with genomic amplification in cell lines, untreated primary tumors, and untreated metastases.

• Proceedings of the Korean Society of Veterinary Pathology Conference
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• 2004.10a
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• pp.5-5
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• 2004

• The Korean Journal of Zoology
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• v.38 no.2
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• pp.196-203
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• 1995

The c-myc proto-oncogene, one of the immediately earlY genes, is expressed in various mammalian cell types and heavily involved in the regulation of cell proliferation and differentiation. To determine endogeneous expression pattern of c-myc gene in preimpBantation mouse embwos, we employed a reverse transcription coupled to polvrnerase chain reaction (RT-PCR). Transcript of c-myc was detected at fertilized embryos as a maternal transcript. At the early two-cell stave, transcript of c-myc gene was hardly detected, bu, appeared at late two-cell embryos as a zygotic transcript. The level of c-myc expresion was increased at later stases and peaked at blastocvst stage. To examine the functional role of promoter region for c-myc gene transcription, we fused the 5'upstream region (1.8 kb) including econ 1 of c-myc genomic DNA with E. coli lacE gene fnamed as pcMYC-laczl. pcMYC-lacZ was microiniected into the pronscleus of mouse one-cell embryovs, and p·salactosidase activity was determined tv histochemical staining with X-gal at different stases. f-galactosidase activity was detected only at blastocyst, but not at the earlier stage embryos. This result indicates that c-myc gene is transcriptionallv active during mouse preimplantation development.

• Korean Journal of Head & Neck Oncology
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• v.18 no.1
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• pp.3-10
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• 2002

Background: The molecular pathogenesis of hereditary medullary thyroid carcinoma is well known to be associated with germ-line mutation in the RET proto-oncogene and sporadic medullary thyroid carcinoma has been shown to carry somatic RET mutation especially in exon 13 and 16. The aim of this study is to evaluate the genetic background in the pathogenesis of the sporadic medullary thyroid carcinoma which shows extremely high incidence in Korea. Materials and Methods: Direct DNA sequencing for RET exon 13 and 16, as well as immunohistochemistrical assay for a monoclonal RET antibody were performed from 20 cases of archival tissues of medullary thyroid carcinoma. Results: Monoclonal RET antibody with C-terminal epitope showed comparatively stronger expression in tumor cells than in normal tissues and immunoreactive area in the tumor was $66.0{\pm}40.1%$. Direct sequencing of RET exon 13 revealed 4 cases of mis-sense mutations in Codon 778, Codon 767, and both in Codon 768 and 778. One case showed a silent mutation (ACG-ACT) in RET exon 16 (Codon 926). Conclusions: The strong RET immunoreactivity of medullary thyroid carcinoma may suggest that there could be a genetic alteration in oncoprotein level. RET proto-oncogene mutation may be involved in the evolutional process of medullary thyroid carcinoma in the aspect of molecular basis.

• Biomolecules & Therapeutics
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• v.16 no.3
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• pp.184-189
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• 2008

The proto-oncogene protein DEK has been implicated in various human disease including cancer. We have shown that DEK induces caspase-dependent apoptosis in Drosophila by regulating histone acetylation. Reverse transcription-polymerase chain reaction (RT-PCR) method based on annealing control primers was used to screen and identify differentially expressed genes (DEGs) in DEK overexpressed HeLa cells. Among the genes identified, clusterin and fibrillarin have major role in apoptosis pathway regulation. TFIIIC and RPS24 are implicated in HAT mediated transcriptional initiation and cololectal cancer, respectively. To further analyze DEK's role in apoptosis, multiplex PCR was performed. Caspase-3, -7, and -10 and proapoptotic gene bid were newly identified as possible target genes regulated by DEK expression.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.16
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• pp.6947-6951
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• 2015

Background: Oral carcinoma (OC) remains one of the most difficult malignancies to cure. Hesa-A is an Iranian herbal-marine compound that has shown promising anti-tumor properties against various human tumors. However, its mechanism of action remains to be addressed. The present study was conducted to evaluate the effect of two doses of Hesa-A on mRNA expression of erb$\backslash$b2 as a main prognosticator tumor marker for OC in an animal model. Materials and Methods: A total of 60 rats were randomly divided into 5 groups of 12 animals each. Rats in carcinoma groups received 0, 250 and 500mg/kg body weight doses of Hesa-A 3 times a day. The other two groups were considered as treated and untreated control groups. At the end of the experiment, animals were sacrificed and tongue tissues subjected to H and E staining and real time PCR. Results: Our results showed that compared to the control group, erb$\backslash$b2 was over-expressed ~ 30% in the carcinoma group. After treatment with 250mg/kg and 500mg/kg body weight of Hesa-A, erb$\backslash$b2 levels dropped by 24.1% and 3.4 % respectively compared to the control carcinoma group (p<0.01, p<0.0001). Moreover, there was a significant relation between erb$\backslash$b2 mRNA content and observed pathological changes in studied groups (p<0.05). Conclusions: These data provide insight into mechanism(s) by which Hesa-A may improve clinical outcome of oral carcinoma by affecting oncogene erb$\backslash$b2 expression and suggest Hesa-A as an effective chemotherapeutic agent in treatment of HER+tumors.

• Toxicological Research
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• v.9 no.2
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• pp.195-206
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• 1993

The expression of proenkephalin (proENK) mRNA and Met-enkephalin (ME) secretion in C6 rat glioma cells and bovine adrenal medullary chromaffin (BAMC) cells were elucidated in the present study. The levels of proENK mRNA and ME secreted into the media in BAMC cells were measured in the presence of cycloheximide and 12-tetrade-canoylphorbol-13-acetate (TPA). Cycloheximide (20 nM) abolished the induction of proENK mRNA expression, protein synthesis and ME secretion by TPA (1nM), indicating that de novo protein synthesis was necessary for proENK gene expression and ME secretion.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.4999-5005
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• 2013

Objective: This study aimed to investigate expression of the proto-oncogene POK erythroid myeloid ontogenic factor (Pokemon) in colorectal cancer (CRC), and assess inhibitory effects of a small interference RNA (siRNA) expression vector in SW480 and SW620 cells. Methods: Semi-quantitative reverse transcription-polymerase chain reaction (PCR) and immunohistochemistry were performed to determine mRNA and protein expression levels of Pokemon in CRC tissues. Indirect immunofluorescence staining was applied to investigate the location of Pokemon in SW480 and SW620 cells. The siRNA expression vectors that were constructed to express a short hairpin RNA against Pokemon were transfected to the SW480 and SW620 cells with a liposome. Expression levels of Pokemon mRNA and protein were examined by real-time quantitative-fluorescent PCR and western blot analysis. The effects of Pokemon silencing on proliferation of SW480 and SW620 cells were evaluated with reference to growth curves with MTT assays. Results: The mRNA expression level of Pokemon in tumor tissues ($0.845{\pm}0.344$) was significantly higher than that in adjacent tumor specimens ($0.321{\pm}0.197$). The positive expression ratio of Pokemon protein in CRC (87.0%) was significantly higher than that in the adjacent tissues (19.6%). Strong fluorescence staining of Pokemon protein was observed in the cytoplasm of the SW480 and SW620 cells. The inhibition ratios of Pokemon mRNA and protein in the SW480 cells were 83.1% and 73.5% at 48 and 72 h, respectively, compared with those of the negative control cells with the siRNA. In the SW620 cells, the inhibition ratios of Pokemon mRNA and protein were 76.3% and 68.7% at 48 and 72 h, respectively. MTT showed that Pokemon gene silencing inhibited the proliferation of SW480 and SW620 cells. Conclusion: Overexpression of Pokemon in CRC may have a function in carcinogenesis and progression. siRNA expression vectors could effectively inhibit mRNA and protein expression of Pokemon in SW480 and SW620 cells, thereby reducing malignant cell proliferation.

• Korean Journal of Oriental Medicine
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• v.12 no.3 s.18
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• pp.131-141
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• 2006

Hominis Placenta has a broad array of clinical applications in Korean medicine, including treatment of inflammatory conditions such as rheumatoid arthritis. The purpose of this study is to explore the global gene expression profiles in human RAW 264.7 cell lines treated with Hominis Placenta herbal-acupuncture solution (HPHAS) using microarray analysis. The RAW 264.7 cells were treated with lipopolysaccharide (LPS), HPHAS, or both. Of the 8,170 genes profiled in this study, with a cut-off level of two-fold change in the expression, 72 genes (CTD1, regulating synaptic membrane exocytosis 2, etc.) were upregulated and 135 genes(splicing factor, arginine/serine-rich 1, actinin, alpha 1, etc.) downregulated following LPS treatment. One gene (acrosin) was upregulated and 12 genes (phospholipase A2, group IB, neurofilament, heavy polypeptide 200kDa, etc.) were downregulated following HPHAS treatment. Eleven genes (RAB27A, member RAS oncogene family, eosinophil peroxidase, etc.) were upregulated and 16 genes (V-maf musculoaponeurotic fibrosarcoma oncogene homolog G (avian), RW1 protein, etc.) were downregulated following co-stimulation of HPHAS and LPS. It is thought that microarrays will play an ever-growing role in the advance of our understanding of the pharmacological actions of HPHAS in the treatment of arthritis. Further studies, however, are required to concretely prove the effectiveness of HPHAS.